How the test is performed: For this test, you must urinate into a special bag or container every time you use the bathroom for 24-hour period.

On day 1, urinate into the toilet when you wake up in the morning. Close the container tightly. Keep it in the refrigerator or a cool place during the collection period.

Urinate into the special container every time you use the bathroom for the next 24 hours.

On day 2, urinate into the container in the morning again when you wake up.

Label the container with your name, the date, the time of completion, and return it as instructed.

For an infant:

Thoroughly wash the area around the urethra (the hole where urine flows out). Open a urine collection bag (a plastic bag with an adhesive paper on one end). For males, place the entire penis in the bag and attach the adhesive to the skin. For females, place the bag over the two folds of skin on either side of the vagina (labia). Put a diaper on the baby (over the bag).

The infant should be checked frequently and the bag changed after the infant has urinated. Empty the urine from the bag into the container provided by your doctor.

Because lively infants can cause the bag to move, this procedure may take a couple of attempts. Extra collection bags may be necessary.

When finished, label and return the container as instructed.

Catecholamines can be also be measured with a blood sample.

How to prepare for the test: A health care provider will tell you whether or not to discontinue any drugs or activities that may interfere with the test.

Certain foods can increase urinary catecholamines, including coffee, tea, bananas, chocolate, cocoa, citrus fruits, and vanilla. Avoid these for several days prior to the test.

Acute stress and vigorous exercise may also affect the test results.

The following drugs can increase catecholamine measurements:

caffeine

acetaminophen (Tylenol)

levodopa

lithium

aminophylline

chloral hydrate

clonidine

disulfiram

erythromycin

insulin

methenamine

methyldopa

nicotinic acid (large doses)

quinidine

tetracyclines

nitroglycerin

Drugs that can decrease catecholamine measurements include:

clonidine

disulfiram

guanethidine

imipramine

MAO inhibitors

phenothiazines

salicylates

reserpine

How the test will feel: The test involves only normal urination, and there is no discomfort.

Why the test is performed: The test is primarily used to diagnose pheochromocytoma and neuroblastoma, and to monitor the effectiveness of their treatments. Urine catecholamine levels are elevated in the majority of neuroblastoma cases.

Catecholamines are small, chemically similar molecules derived from the amino acid tyrosine. The major catecholamines are dopamine, norepinephrine, and epinephrine (old name: adrenalin).

All of the catecholamines are broken down by their target tissues (such as the brain) or by the liver and become inactive substances that appear in the urine: